A number of components on-board an aircraft require electrical power for their activation. Many of these components are separate from the electrical components that are actually required to run the aircraft (i.e., the navigation system, fuel gauges, flight controls, and hydraulic systems). For example, aircraft also have catering equipment, heating/cooling systems, lavatories, power seats, water heaters, and other components that require power as well. Specific components that may require external power include, but are not limited to, trash compactors, ovens and warming compartments (e.g., steam oven, convection oven, bun warmer), optional dish washer, freezer, refrigerator, coffee and espresso makers, water heaters (for tea), air chillers and chilled compartments, galley waste disposal, heated or cooled bar carts/trolleys, surface cleaning, area heaters, cabin ventilation, independent ventilation, area or spot lights (e.g., cabin lights and/or reading lights for passenger seats), water supply, water line heating to prevent freezing, charging stations for passenger electronics, electrical sockets, emergency lighting, and combinations thereof.
However, one concern with these components is their energy consumption. As discussed, galley systems for heating and cooling are among several other systems aboard the craft which simultaneously require power. Frequently, such systems require more power than can be drawn from the aircraft engines' drive generators, necessitating additional power sources, such as a kerosene-burning auxiliary power unit (“APU”) (or by a ground power unit if the aircraft is not yet in flight). This power consumption can be rather large, particularly for long flights with hundreds of passengers. Additionally, use of aircraft power produces noise and CO2 emissions, both of which are desirably reduced, as well as typically requiring fossil fuels for operation.
Typically, galley feeders are sized for max load and safety margin load, in which all electrical Galley Inserts (“GAINs”) are running at max load simultaneously. Currently, there is no intelligent system distributing power to individual GAINs. Rather, the crew controls the power distribution to determine which equipment is operated when and in what combination, as shown in the control panel 50 in FIG. 1, which provides flexibility to meet customers' needs but does not optimize galley power consumption.
Accordingly, it is desirable to identify ways to improve fuel efficiency and power management by providing innovative ways to power these components and distribute loads among GAINs.
Further, a number of systems on-board an aircraft require water for their use. Galleys are connected to the aircraft potable water tank, and water is required for many of the related on-board services. Water pipes connect the water tank to the water consumers. For example, coffee cannot be made, hand-washing water is not provided, and so forth, until the APU or electrical switch is on in order to allow water to flow. Some examples of the water consumers on-board aircraft are the steam oven, beverage maker (coffee/espresso/tea), water boiler, tap water supply, and the dish washer. Aircraft typically carry large amounts of potable water in the potable water tanks, which is uploaded when the aircraft is on the ground. A number of water saving attempts have been made to help re-use certain types of water onboard aircraft, but it is still desirable to generate new ways to generate and/or re-use water on-board aircraft. Other systems use heat, which is also typically generated by separate units. For example, heated water is desirable for use in warming hand-washing water (and to prevent freezing of the water pipes), the ovens and warmers onboard require heat, as well as the cabin heating units.
The present inventors have thus sought new ways to generate power to run on-board components, as well as to harness beneficial by-products of that power generation for other uses on-board passenger transport vehicles, such as aircraft.
The relatively new technology of fuel cells provides a promising cleaner and quieter means to supplement energy sources already aboard aircrafts. A fuel cell has several outputs in addition to electrical power, and these other outputs often are not utilized. Fuel cell systems combine a fuel source of compressed hydrogen with oxygen in the air to produce electrical and thermal power as a main product. Water and oxygen depleted air are produced as by-products, which are far less harmful than CO2 emissions from current aircraft power generation processes.